Since SELD consists of both SED and DOAE tasks, it inherits many challenges from both SED and DOAE, such as noise, reverberation, interference, polyphony, and non-stationarity of sound sources. Furthermore, SELD often faces an additional challenge in correctly associating SED and DOAE outputs of multiple overlapping sound events. In an attempt to dissect the difficulties of the SELD task, Politis et al. compared the performances of the same SELD system in different acoustic environments [1]} with different combinations of noise, reverberation, and unknown interferences. The authors founded that, in absence of unknown interferences, ambiance noise has little negative effects on SELD performance, while reverberation significantly reduces the SELD performance in all noise combinations. Unknown interferences degrade SELD performances by the largest margin compared to noise and reverberation. In addition, using the FOA format generally produces better performance than the MIC format.
